Fuels containing dicyclomatic dinickel acetylenes



United States Patent O.

This application is a division of application Serial No 852,216, filed November 12, 1959, now US. 3,097,224, July 9, 1963.

This invention relates to novel organometallic compounds and their mode of preparation. More specifically, this invention relates to bis(cyclomatic nickel) acetylene compounds wherein each nickel atom is bonded 'to a cy-.

clomatic hydrocarbon group, to another nickel atom,

and to an acetylene compound which is bonded to both of the two nickel atoms.

It is an object of this invention to provide a novel class of bis(cy:clomatic nickel) acetylene compounds. A further object is to provide a process for the preparation of these compounds. Another object is to provide fuel -antiknock mixtures wherein a bis(cyclomatic nickel) acetylene compound is present as a primary antiknock or as a supplemental antiknock in addition to another antiknock material. Additional objects of this invention will become apparent from a reading of the specification and claims which follow.

The objects of this invention are accomplished by providing compounds represented by the formula:

matic hydrocarbon groups which donate five electronsto the nickel atoms for bonding. By virtue of the electrons donated to each of the nickel atoms from the cyclomatic hydrocarbon groups, the acetylene molecule and the other nickel atom, each of the nickel atoms presentin the compounds of my invention, achieves the inert gas electron configuration of krypton.

The cyclomatic hydrocarbon groups, designated by the symbols Cy and Cy' in the above formula, may be, the

same or different and are cyclopentadienyl-typehydro;

Bythis, it is meant that the radical In general, such carbon radical-s. contains the cyclopentadienyl moiety. cyciomatic hydrocarbon groups can the formulae:

wherein the Rs are selected from the group consisting of hydrogen and univalent hydrocarbon radicals.

A preferred class of cyclomatic radicals suitableinthepractice of my invention are those which contain from five to about 13 carbon atoms. These are exemplified by cyclopentadienyl, indenyl, methyl cyclopentadienyl, propylcyclopentadienyl, diethylcyclopentadienyl, phenylcybe represented by 3,246,966 Patented Apr. 19, 1966 clopentadienyl, tert-butyl cyclopentadienyl, p-ethylphenyl cyclopentadienyl, 4- tert-butyl indenyl and the like. The compounds which yield these radicals are preferred as they are the more readily available cyclomatic compounds, and the compounds of my invention containing these radicals have the more desirable physical characteristics which render them of superior utility.

As shown in the above formula, the bridging acetylenetype molecule is believed to be bonded to both of the nickel atoms in forming the compounds of my invention.

' As visualized, the triple bond in the bridging acetyleniccompoundis reduced to a single bond thus making four electrons available for bonding to the two nickel atoms.- Each of the carbon atoms on either side of the triple bond is thereby bonded to each of the nickel atoms. The

' actual configuration of the bridging acetylenic molecule about 10 carbon atoms.

is believed to be approximately at right angles to the plane in which the two inter-connected nickel atoms lie. This is shown in the above formula by means of the dotted lines indicating bonding of thelcarbon atom which is behind the plane of the paper ,to the two nickel atoms illustrated as lying in the plane of the paper. The other carbon atom which is bonded to the two nickel atoms formula, may be the same or different and are hydrogen or univalent hydrocarbon groups containing from one to cals within this range impart'desirable physical'properties:

to the compounds of my invention.

Q and Q may also be an aryl radical, either a fused or' single ring, such as phenyl, tolyl, xylyl, naphthyl or the like. In addition, Q and Q may be hydrocarbon groups containing unsaturated double bonds such as 'alkenyl-or; cycloalkenyl radicals.

Typical of such radicals are bu tenyl, pentenyl, hexenyl, nonenyl, cyclohexenyl, cyclo pentenyl and the like. In addition, the Q groups may be alkarylradicals, aralkyl radicals, and cycloalkyl radicals" containing up to about 10 carbon atoms. Typical of such radicals are vbenzyl, phenylethyl, phenylpropyl, phenylbutyl, cyclohexyl, cyclopentyl, cycloheptyl, cyclode cyl, p-ethylphenyl m-butylphenyl, p-methylphenylzand the like.

Although the Q groups, as defined above, are univalent hydrocarbon radicals or hydrogen, thesegroups may be substituted with polar sub stituent s which preferably should be separated by at least two carbon atoms from the triple acetylenic bond to avoid cumbersome side reactions. Typical acetylenic compounds containing suchnon-reactive non-hydrocarbon substituent groups are perhalo butynes, propargyl alcohol, ethynyl cyclohex-anol, beta heptynes, S-methoxy pentyne-l, and the like.

The method by which my compounds are formed involves the following chemicalreaction:

This reaction may, in general, be carried out between v The pressure at which the reaction is carried out is, in general, not critical. If the acetylenic reactant is a Q and Q are preferably alkyl 3 gas, however, the pressure should be sulficiently high to insure that a goodlyv percentage of the gaseous acety lenic reactant is dissolved in the solution comprising the bis(cyclomatic) nickel reactant and a solvent. Since it is necessary for the gaseous acetylenic reactant to contact the bis(cyclomatic) nickel compound'in order for reaction to take place, pressure will, in this instance, have a substantial effect on the reaction rate. In general, pressures between about atmospheric and about 10,000 p.s.i.g., may be employed. It the acetylenic reactant is acetylene itself, it is preferable not to exceed reaction pressures of 250 p.s.i.g. since above this pressureacetylene is difiicult to handle and may explode causing considerable damage to the reaction vessel. A preferred pressure range is between about atmospheric to about 250 p.s.i.g. since within this range high yields are obtainable without the expense and safety precautions necessitated by the use of,

matic) nickel compound is fairly soluble may be employed. Typical of such solvents are high boiling saturated hydrocarbons such as n-octane, n-decan'e, and other paraflinic hydrocarbons having up to about 20 carbon atoms such as eicosane, pentadecane and the like. Also applicable are aromatic solvents such as benzene, toluene, rnesitylene, and the like. Typical ether solvents are ethyl octyl ether, ethyl hexyl ether, diethylene glycol methyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol dietheyl ether, trioxane, tetrahydrofuran, ethylene glycol dibutyl ether and the like. Ester solvents which may be employed include pentyl butanoate, ethyl decanoate, ethyl hexanoate, and the like. Silicone oils such as the dimethyl polysiloxanes, bis(chlorop-henyl) polysiloxanes, hexapropyldisilane, and diethyldipropyldiphenyldisilane may also be employed. Other ester solvents are those derived from succinic, glutaric, adipic, pimelic, suberic, azelaic, sebacic and pinic acids. Specific examples of such esters are di-(Z-ethylhexyl) adipate, di-(2 ethylhexyl) azelate, di-(Z-ethylhexyl) sebacate, di-(methylcyclohexyl) adipate and the like. Preferred solvents are the polar ethers such as diethylene glycol dimethyl etherv and tetrahydrofuran.

A further criteria for the solvent is that it be one which is easily separable from the compounds formed in the process. If, for example, the product is a liquid as in the case of bis(cyclopentadienyl nickel) hexyne-3, the solvent should be selected so that it has a normal boiling point differing by at least 20 C. from the normal boiling point of the liquid product. Use of such a solvent enables separation of the product by means of distillation. selected .so. that its freezing point is sufiiciently low so as to enable separation of the product therefrom by means of crystallization.

The time required for my process will vary in accordance-withthe other reaction-variables. It generally takes from about 30 minutes to about 20 hours, however.

Although not critical, it is generally desirable to agitate the reaction mixture when carrying out my process. Agitation, especially if the reactants are not mutually soluble in the reaction solvent, insures a homogeneous reaction mass and an even reaction rate. Obviously, both conditions are desirable since they increase the efliciency of the process.

In order to insure high yields of product, based on the more expensive bis(cyclomatic) nickel reactant, it is pref.- erable in my process to use excess quantities of the acetyle'nic'rcactant. In general, Iemploy from about 0.75 to about 30 moles of acetylenic reactant for each mole of bis(cyclomatic) nickel reactant. Higher or lower quanti tics Qfthc acetylenic reactant may be used but, in general,

If the product is a solid, the solvent should be d I find that quantities within this range insure a relatively high'yield of product.

As previously set forth, -my invention embraces a variety of bis(cy-clomatic nickel) acetylenic compounds. Typical of these compounds are bis(cyclopentadienyl nickel) acetylene, bis(cyclopentadienyl nickel) propyne, bis(cyclopentadienyl nickel) pcntyne-l, bis(cyclopentadienyl nickel) butyne-l; bis(cyclopentadienyl nickel) phenylacetylene, bis(cyclopentadienyl nickel) diphenylacetylene, bis(cyclopentadienyl nickel) butyne-2, bis(cyclopentadienyl nickel) hexyne-3, bis(cyclopentadienyl nickel) perfluorobutyne-2, bis(cyclopentadienyl nickel) decyne-S, bis(methylcyclopentadienyl nickel) octyne-4, bis(indenyl nickel) hexyne-.1, bis(cyclopentadienyl nickel) octodecyne-9, bis(cyclopentadienyl nickel) proparg'yl alcohol, cyclopentadienyl nickel methyl cyclop'entadienyl nickel hexyne-3, and the like.

Preferably, the process is carried out under a protective atmosphere of an inert gas such'as nitrogen, helium,

argon and the like. This prevents decomposition of the reactants and/or products and results in the obtaining of higher yields.

- To further illustrate my compounds and their mode of preparation, there are presented the following examples in which all pants and percentages are by weight unless otherwise indicated.

EXAMPLE I To 20 parts of nickclocene were added 710 parts of anhydrous tetrahydrof-uran to form a solution which was sealed in a stainless steel autoclave. Acetylene was added to the autoclave until an equilibrium pressure of p.s.i.g. was attained over the solution. The autoclave was then pressurized to 2,000 p.s.i.g. with pure nitrogen. The

i reaction mixture was heated for two and one-half hours at 70 C. and allowed to cool overnight. It was then discharged from the autoclave under nitrogen. On filtering, two parts of amorphous decomposition product was separated from the reaction mixture. The solvent was then removed from the remaining reaction mixture under reduced pressure to leave a dark-green residue. The residue was triturated with a small volume of petroleum ether to remove oil-like contaminants, and the residue was sublimed at 0.05 mm. Hg and room temperature to give 12 parts of nickelocene having a melting point of l72173 C. When sublimation appeared to have ceased, the temperature was raised to 60 C. This caused further sublimation to yield a dark-green solid su-blimate. Repeated fractional sublimation followed by recrystallization from petroleum ether yielded 0.5 part of a flaky, light-green lustrous solid having a melting point of 143 C. This solid was analyzed and found to be bis(cyclopentadienyl nickel) acetylene. Analysis.Found: C, 52.3; H, 4.49; Ni, 42.6. Calculated for (C H Ni) HCECI-I: C, 52.7; H, 4.39; Ni, 42.9.

. EXAMPLE II was bubbled through the solution with moderate stirring.

The reaction systernwas maintained under these conditions for approximately 12 hours after which the system was cooled. The reaction product was filtered to remove some black decomposition product. The black decomposition product was throughly washed with low-boiling petroleurn ether and the washings were kept separate from thefiitrate. The filtrate was cooled to 70 C. yielding green crystals which were filtered off under nitrogen and washed with cold petroleum ether. The washed crystals were then sublimed at 0.05 mm. Hg and room temperature to give three parts of nickelocene having a melting point o-f 172-173" C. When the nickelocene had ceased to sublime, the temperature of the sublimator was raised to 60 C. which caused the sublimation of 0.7 part of a darkgreen solid. This solid was recrystallized from petroleum ether to yield flaky green crystals having a melting point of 142-143 C. with decomposition. An additional 3.1 parts of nickelocene and 0.3 part of the flaky green crystals melting at 143 C. were recovered from the d-imethyl carbitol filtrate by dilution with water, extraction with benzene and fractional sublimation. Evaporation of the petroleum ether washings followed by fractional sublimation yielded an additional 1.0 part of nickelocene and 0.2 part of product. On analysis, the flaky green crystals melting at 142-143 C. were found to be bis(cyclopentadienyl nickel) acetylene. The total yield of this compound was 1.2 parts.

= I EXAMPLE III brown residue which was triturated with about 320 parts.

of low boiling petroleum ether. Removal of the ether solvent followed by repeated fractional sublimation of the residue and recrystallization of the dark-green condensate from petroleum ether yielded about 0.3 part of a flakygreen solid having a melting point of 142-143 C. .with

decomposition. This product was found to have an in-,

frared spectrum which was identical to the infrared spectrum of bis(cyclopentadienyl nickel) acetylene as prepared in the previous examples. This proved conclusively that the product obtained was bis(cyclopentadienyl nickel) acetylene.

EXAMPLE IV A solution comprising 20 parts of nickelocene in 710 parts of tetrahydrofunan was charged to a stainless steel autoclave. The autoclave was pressurized to an equilibrium pressure of 85 p.s.i.g. with acetylene, and the reaction mixture was heated at 45 C. for approximately 100 hours. The autoclave was discharged, and the reaction mixture was filtered. Excess solvent was stripped off under reduced pressure without heating' The green crystalline fractions, which separated as the volume of the solution and the temperature decreased, were filtered under nitrogen and'fractionally sublimed at 0.05 mm. Hg. A total of 12.6 parts of unreacted nickelocene and 1.2 parts of bis(cyclopentadienyl nickel) acetylene were isolated. The bis(cyclopentadienyl nickel) acetylene had a melting pointof 141-142? C. and was identical to the.

bis(cyclopentadienyl nickel) acetylene as prepared in the previous examples. I

EXAMPLE V A solution comprising 20 parts of nickelocene dissolved in 622 parts of anhydrous tetrahydrofuran was charged to a stainless steel autoclave along with 100 parts of propyne. The reaction mixture was heated at 85 C. for four and one-half hours after which the reaction vessel was cooled to room temperature. The vessel was then discharged, and the reaction product was filtered. The solvent was removed at room temperature under reduced pressure,

and the dark-green residues were triturated with approximately 38.4 parts of petroleum ether and filtered. Sublimation of the triturate residues at room temperature and 005mm. Hg yielded 11 parts of nickelocene, The petroleum ether solubles from the sublimation residues were combined with the dark-green triturate liquors, and the whole was chromatographedon alumina and eluted with petroleum ether. This procedure enabled separation of a 6 dark-green crystalline solid from small amounts of nickelocene in the eluate, Repeated chromatography of the dark-green solid followed by fractional sublimation yielded 2.1 parts of dark-green needle-like crystals having a melting point of '6869 C. which on analysis was found to be bis(cyclopentadienyl nickel) propyne. On analysis, there was found: C, 53.7; H, 4.54; Ni, 40.3. Calculated for (C H Ni) HCECCH C, 54.3; H, 4.87; Ni, 40.8. p

EXAMPLE VI Four parts of nickelocene, seven parts of 3-hexyne and 8.9 parts of tetrahydrofuran were charged to a reaction vessel and heated at C. for 15 hours. The reaction vessel was then cooled and discharged. Excess tetrahydrofuran was removed under reduced pressure at room temperature. The dark-green oily residue was dissolved in petroleum ether and chromatographed on alumina. Elution with petroleum ether gave poor resolution of the dark-green product-band from traces-of unreacted nickelocene. Removal of excess petroleum ether from the center cut of the dark-green product band yielded a lightgreen residue which was evaporatively distilled at 0.05 mm. Hg and 50 C. YRepeated chromatographic purification followedby evaporative distillation failed to cause crystallization at room temperature. The dark-green liquid possessed infrared absorbencies in the nine to 13 micron regions characteristic of bis(c'yclopentadienyl nickel) acetylene. On analysis, the dark-green liquid product (2.4 parts) was found to be bis(cyclopentadienyl nickel) hexyne3. Analysis-Found: C, 58.6; H, 6.21; Ni, 35.4.

Calculated for (C H Ni) C H CECC H C, 58.3; H,

6.10; Ni, 35.6 percent. M 7

' EXAMPLE v11 v To 18 parts of nickelocene and 534 "parts of tetrahydrofuran in an autoclave was added sufiicient acetyleneto raise the equilibrium pressure to p.s.i.g. The reacti-onirnixture was heated for 16 hours at 80 C. The autoclave was then discharged, and the reaction product was filtered. The solvent was removed at room temperature under reduced pressure. The green residue was triturated with about 64 parts of petroleum ether to remove oily contaminants. The residue was then fractionally sublimed at 0.01 mm. Hg. 'During' the sublimation, unreacted ni-ckelocene was sublimed at room temperature whereas the product, bis'(cyclopentadienyl nickel) acetylene, required a sublimation temperature of 60 C. I Additional nickelocene and productwas also isolated from the petroleum ether triturates' by means of chromatogra- The total yield of bis(cyelopentadienyl phy on alumina. nickel) acetylene, having a melting point of 142-143 C., was 6.3 parts which corresponds to a yield of 71 percent.

EXAMPLE vnr Five parts of nickelocene, 10 parts of l-pentyne and ;matographic purification of the material on alumina, us-

ing petroleum ether eluant, removed traces of an oily contaminant. Resublimation of the chromatographed solid gave 1.'1 parts of bis(cyclopentadienyl nickel) 1- pentyne which was a dark-green solid having a melting point of 50-51 C. 'On analysis, there was found: C,

56.4; H, 5.67; Ni,'3.6.6. Calculated for c, 17.0; H, 5.80; Ni, 37.2 percent.

' EXAMPLE IX Fifteen parts of nickelocene and 32 parts of Z-butyne were dissolved in 534 parts of tetrahydrofuran. The solution was charged to a stainless steel autoclave and heated at 115 C. for 20 hours. The autoclave was then cooled, and the reaction product was discharged. The reaction product was filtered, and solvent was removed under reduced pressure. The green reaction residue was triturated with about 96 parts of petroleum ether and chromatographed on alumina. Elution with petroleum ether gave a good separation of unreacted nickelocene from the product band. The product band was stripped of solvent and sublimed at 0.05 mm. Hg at 40 C. This resulted in the isolation of 6.4 parts of unreacted nickelocene and 3.7 parts of bis(cyclopentadienyl nickel) 1- butyne which was a dark-green solid having a melting point of 5657 C. On analysis, there was found: C, 56.0; H, 5.80; Ni, 38.7. Calculated for 2CH3C E C, 55.7; H, 5.35; Ni, 38.9 percent.

EXAMPLE X A solution of 5.0 parts ofnickelocene and 10 parts of ethynyl benzene in 2 6.6 parts of tetrahydrofuran was heated at reflux for 30 minutes under a protective atmosphere of nitrogen. The solvent and unreacted ethynyl benzene were then removed under reduced pressure, and the reaction residue was triturated with low-boiling petroleum ether. The triturates were chromatographed on alumina and eluted with petroleum ether. This procedure yielded one part of unreacted nickelocene. The remaining reaction residues were fractionally sublimed at 0.05 mm. Hg, and an additional 1.5 parts of unreacted nickelocene was obtained. On increasing the temperature of the sublimator to 60 0., there was obtained 0.8 part of bis(cyclopentadienyl nickel) phenylacetylene which was a dark-green solid that crystallized from isooctane as dark-green needles having a melting point of 132 C. On analysis, there was found: C, 61.2; H, 4.6; Ni, 33.3. Calculated for (C H Ni) I-ICECC H C, 61.8; H, 4.6; Ni, 33.5 percent.

EXAMPLE XI A solution of two parts of nickelocene and two parts of perfluorobutyne-Z in 20 parts of tetrahydrofuran was allowed to stand at room temperature for 70 hours. The viscous reaction mixture was relieved of the volatile solvent at reduced pressures, and the residue was sublimed at 0.02 mm. Hg and 40 C. The sublirnate was triturated with low-boiling petroleum ether, and the trimrates were chromatographed on alumina and eluted with petroleum ether. This procedure resulted in the recovery of 1.2 parts of nickelocene and 0.05 part of a dark-green crystalline material having a melting point of 93 C. This product was identified as his (-cyclopentadienyl nickel) perfluorobutyne-2 through its elemental analysis and a comparison of its infrared spectrum with the similar infrared spectra of other bis(cyclopentadienyl nickel) alkyne compounds of my invention.

EXAMPLE XII A solution of four parts of nickelocene and three parts of diphenylacetylene in 50 parts of toluene was refluxed for 10 hours. Excess solvent was removed under reduced pressure, and unreacted nickelocene and diphenylacetylene were sublimed out of the reaction mixture under reduced pressures at 50 C. The residue was triturated with petroleum ether, and the triturate was filtered and chilled to Dry Ice temperatures where crystallization occurred. On recrystallization from petroleum ether, there was obtained one part of bis(cyclopenta- 8. dienyl nickel) diphenylacetylene having amelting point of 148 C. The compound was clearly identified as bis(cyclopentadienyl nickel) diphenylacetylene through means of an elemental analysis and the infrared spectrum of the compound which closely resembled those of my other bis(cyclopentadienyl nickel) alkyne compounds.

EXAMPLE XIII A solution of 0.2 mole of nickelocene and 0.15 mole of decyne-S is dissolved in isooctane and heated in a sealed vessel at 120 C. for 10 hours. Excess solvent is removed under reduced pressure, and the residue is taken up in low-boiling petroleum ether, chromatographed on alumina, and eluted with petroleum ether. This results in a good yield of bis(cyclopentadienyl nickel) decyne-S with an infrared spectrum characteristic of the his (cyclopentadienyl nickel) alkyne compounds.

EXAMPLE XIV A solution of one mole of bis(methyl cyclopentadienyl) nickel and two moles of octyne-4 in ethyl acetate solvent is heated in a sealed vessel at 85 C. for 10 hours. Excess solvent is removed under reduced pressure; the residue is taken up in low-boiling petroleum ether, chromatographed on alumina and eluted with petroleum ether.

This enables the isolation of a good yield of bis(methyl cyclopentadienyl nickel) octyne-4 with an infrared spectrum characteristic of the bis(cyclopentadienyl nickel) alkyne compounds.

EXAMPLE XV A solution of 0.05 mole of bis(indenyl) nickel and 1.5 moles of hexyne-l is heated in a closed vessel at C. for 10 hours. Excess hexyne-l is removed under reduced pressure, and the residue is taken in petroleum ether and chromatographed on alumina and eluted with reduced pressure, and the residue is taken up in petroleum hexyne-l is obtained.

A further embodiment of the present invention comprises the use of the compounds of my invention as antiknock agents in a liquid hydrocarbon fuel used in spark ignition internal combustion engines. For this use, I provide a liquid hydrocarbon fuel of the gasoline boiling range containing from about 0.05 to about 10 grams per gallon of nickel as a compound of my invention. It is found that these compositions, when employed as fuels for a spark ignition internal combustion engine, greatly reduce the tendency of the engine to knock.

A preferred composition of my invention comprises a hydrocarbon of the gasoline boiling range containing from about 1.0 to about 6.0 grams of metal per gallon of fuel as a nickel compound as defined previously. This range of metal concentration is preferred since it is found that superior fuels results from its employment.

A further preferred class of compositions of my invention comprises hydrocarbon fuels containing a bis(cyclomatic nickel) acetylenic compound wherein the bridging acetylenic group contains from four to 10 carbon atoms. A still further preferred class of compositions are those in which the bridging acetylenic group contains six carbon atoms. A most preferred composition is that containing bis(cyclomatic nickel) hexyne-3 since these compounds are found to be most excellent antiknock additives.

The base fuels used to prepare the compositions of my invention have a wide variation of compositions. They generally are petroleum hydrocarbons and are usually blends of two or more components containing a mixture of many individual hydrocarbon compounds. These fuels can contain all types of hydrocarbons, including paraffins, both straight and branched chain; olefins; cycloaliphatics containing paraffin or olefin side chains; and aromatics containing aliphatic side chains. The fuel type depends on the base stock from which is obtained and on the method of refining. For example, it can be a straight run or processed hydrocarbon, including thermally cracked, catalytically cracked, reformed fractions, etc. When used for spark-fired engines, the boiling range of the components in gasoline can vary from zero to about 430 F., although the boiling range of the fuel blend is often found to be between an initial boiling point of from about 80 F. to 100 F., and a final boiling point of about 430 F. While the above is true for ordinary gasoline, the boiling range is somewhat more restricted in the case of aviation gasoline. Specifications for the latter often call fora boil-ing range of from about 82 F. to about 338 F., with certain fractions of the fuel boiling away at particular intermediate temperatures.

These fuels often contain minor quantities of various impurities. One such impurityjis sulfur, which canbe present either in a combined form as an organic or inorganic compound, or as elemental sulfur. The amounts of such sulfur can vary in various fuels about 0.003 percent to about 0.30 percent by weight. Fuels containing quantities of sulfur, both lesser and greater than the range of amounts referred to above, are also known. These fuels also often contain added chemicals in the nature of antioxidants, rust inhibitors, dyes, and the like.

The bis(cyclomatic nickel) acetylenic compounds of my invention can be added directly to the hydrocarbon fuel, and the mixture then subjected to stirring, mixing or other means of agitation until a homogeneous fluid results. In addition to the bis(cyclomatic nickel) acetylenic compounds, the fuel may have added thereto antioxidants, metal deactivators, halohydrocarb on scavengers, phosphorus compounds, anti-rust and anti-icing agents, and supplementary wear inhibitors. The following examples are illustrative of improved fuels of my invention containing a bis(cyclomatic nickel) acetylenic compound, and also a method for preparing said improved fuels.

EXAMPLE XVI the fuel is achieved. This fuel has substantially increasedoctane value.

EXAMPLE XVII To 1000 gallons of commercial gasoline having a gravity of 59.0 API, an initial boiling point of 98 F. and a final boiling point of 390 F. which contains 45.2 volume percent parafiins, 28.4 volume percent olefins and 25.4 volume percent aroma-tics is added 10.0 grams per gallon of nickel as bis(cyclopentadienyl nickel) pentyne-l to give a fuel of enhanced octane quality.

EXAMPLE XVIII Bis(cyclopentadienyl nickel) diphenylacetylene is added in amount suflicient to give a nickel concentration of 6.0 grams per gallon to a gasoline having an initial boiling point of 93 F., a final boiling point of 378 F. and an API gravity of 562.

EXAMPLE XIX To a liquid hydrocarbon fuel containing 49.9 volume percent pa-rafiins, 15.9 volume percent oletins and 34.2 volume percent aromatics and which has an API gravity of 51.5", an initial boiling point of 11 F. and a final boiling point of 394 F. is added bis(cyclopentadienyl nickel) acetylene to a nickel concentration of 3.0 grams per gal- .lon.

EMMPLE XX To the fuel of Example XIX is added bis(indenyl nickel) decyne-3 in amount such that the nickel concentration is 2.0 grams per gallon.

A further embodiment of the present invention comprises a liquid hydrocarbon fuel of the gasoline boiling range containing an organolead antiknock agent and in addition a bis(cyclomatic nickel) acetylenic compound as defined previously. In this embodiment of the invention, it is often desirable that the fuel contain also conventional halohydrocarbon scavengers or corrective agents as conventionally used with organolead antiknock agents. When an organolead antiknock agent is employed, it may be present in the fuel in concentrations up to about eight grams of lead per gallon. In the case of aviation fuels, up to 6.34 grams of lead may be employed.

For each gram of lead, there may be present from' about 0.008 to about 10 grams of nickel as a bis(cyclomatic nickel) acetylenic compound. A preferred range comprises those compositions containing from about 0.1 to about six grams of nickel as a bis(cyclomatic nickel) acetylenic compound for each gram of lead as an organolead compound.

A preferred embodiment of my invention comprises a liquid hydrocarbon fuel of the gasoline boiling range containing from about 0.5 to about 6.34 grams of lead per gallon as an organolead antiknock agent andfrom about 0.008 to about one gram of nickel per gallon as.

a bis(cyclomatic nickel) acetylenic compound as defined above. A further preferred aspect of my invention comprises compositions, as defined previously, in which the nickel concentration ranges from about 0.01 to about 0.5 and most preferably from about 0.01 to about 0.3 gram.

of nickel per gallon- These ranges of metal concentrations are preferred as it has been found that especially superior fuelsparticularly from a cost-effectiveness The organolead antiknock agents are ordinarily hydro carbolead compounds including tetraphenyllead, dimethyldiphenyllead, tetrapropyllead, dimethyldiethyllead, tetramethyllead and the like. Tetraethyllead is preferred as 'it is most commonly available as a commercial antiknock agent. It is also convenient in the case Where organolead antiknock agents are employed to premix into a fluid the bis(cyclomatic nickel) acetylene compound, the organo-.

example, lead dihalide. In other words, a theory of halogen represents two atoms of halogen for every atom of lead present. In like manner, a theoryof phosphorus is the amount of phosphorus required to convert the lead l present to lead orthophosphate, Pb (PO that is, a" theoryv of phosphor-us represents two atoms of phosphorus for every three atoms of lead. One theory of arsenic,

antimony and bismuth is defined in the same general way. i That is, one theory thereof is two atoms of the element per each three atoms of lead.

The halohydrocarbon scavengers which can be employed in the compositions of this invention can be either aliphatic or aromatic halohydrocar'bons or a combination Most preferably, the bridging acetylenic group.

These coml. l of the two having halogen attached to carbon in either the aliphatic or aromatic portion of the molecule. The scavengers may also be carbon, hydrogen and oxygen containing compounds, such as haloalkyl ethers, halohydrins, halo ethers, h'alonitro compounds, and the like. Still other examples of scavengers that may be used in the fuels of this invention are illustrated in US. Patents 1,592,954; 1,668,022; 2,398,281; 2,479,900; 2,479,901;

2,849,302; 2,849,303; and 2,849,304. Mixtures of different scalvengers may also be used and other scavengers and modifying agents, such as phosphorus compounds, may also be included. Concentrations of organic halide scavengers ranging from about 0.5 to about 2.5 theories based on the lead are usually sufiicient, although greater or lesser amounts may be used. See, for example, the description of scavenger concentrations and proportions given in US. Patent 2,398,381. Such concentrations and proportions can be successfully used in the practice of this invention.

When used in the compositions of this invention, phosphorus, arsenic, antimony and bismuth compounds have the property of altering engine deposit characteristics in several helpful ways. Thus, benefits are achieved by including in the compositions of this invention one or more gasoline-soluble organic compounds of the elements of Group VA of the Periodic Table, which elements have atomic numbers through 83. The Periodic Table to which reference is made is found in Langes Handbook of Chemistry, 7th edition, pages 58-59. One eifect of these Group VA compounds is to alter the deposits so that in the case of spark plugs the resulting deposits are less conductive. Thus, imparted to the spark plug is greater resistance to fouling. In the case of combustion chamber surface deposits, the Group VA element renders these deposits less catalytic with respect to hydrocarbon oxidation and thus reduces surface ignition. In addition, these Group VA elements in some way inhibit deposit build up on combustion chamber surfaces, notably exhaust valves. This. beneficial effect insures excellent engine durability. In particular, excellent exhaust valve life is assured. Of these Group VA elements the use of gasoline-soluble phosphorus compounds is preferred from the cost-effectiveness standpoint. Applicable phosphorus additives include the general organic phosphorus compounds, such as derivatives of phosphoric and phosphorus acids. Representative examples of these compounds include trimethylphosphate,

trimethylphosphite, phenyldimethylphosphate, triphenylphosphate, tricresylphosphate, tri-ochloropropyl thionophosphate, tributoxyethylphosphate, xyly-l dimethylphosphate, and other alkyl, aryl, aralkyl, alkaryl and cycloalkyl analogues and homologues of these compounds. Phenyldimethylphosphates in which the phenyl group is substituted with up to three methyl radicals are particularly preferred because they exhibit essentially no antagonistic effects upon octane quality during engine combustion. Other suitable phosphorus compounds are exemplified by dixylyl phospho-ramidate, tributylphosphine, triphenylphosphine oxide, tricresyl thiophosphate, cresyldiphenyl phosphate, and the like. Gasoline-soluble compounds of arsenic, antimony and bismuth corresponding to the above phosphorus compounds are likewise useful in this respect. Thus, use can be made of various alkyl, cycloalkyl, 'aralkyl, aryl and/ or alkaryl, arsenates, arsen-ites, antimonates, antimonites, bismuthates, bismuthites, etc. Tricresyl arsenite, tricumenyl arsenate, trioctyl antimonate, triethyl antimonite, diethylphenyl bismuthate and the like serve as examples. Other very useful arsenic, antimony and bismuth compounds include methyl arsine, trimethyl arsine, triethyl arsine, triphenyl ars-ine, arseno benzene, triisopropyl bismuthine, tripentyl stibine, tricresyl stibine, trixylyl bismuthine,

tricyclohexyl bismuthine and phenyl dicresyl lbismuthine.

From the gasoline solubility and engine inductibility standpoints, organic compounds ofthese' Group VA elements having up to about 30 carbon atoms'in the molecule are preferable. Concentrations of these Group VA compounds ranging from about 0.05 to about one theory based on the lead normally sufiice. In other Words, the foregoing technical benefits are achieved when the atom ratio of Group VA element-to-lead ranges from about 0.1:3 to about 2:3.

A further embodiment of my invention comprises antiknock fluids containing an organolead antikn-ock agent, a bis(cyclomatic nickel) acetylenic compound, and, optionally, a scavenger for the organolead compound. The quantities of nickel compound and scavenger present with respect to the quantity of lead present are the same as set forth in the preceding paragraphs in describing a hydrocarbon fuel containing these various components. Thus, the fluid can be blended with ahydrocarbon base fuel to give the fuel compositions described above.

The following examples are illustrative of fuels and fluids containing organolead compounds in combination with various bis (cyclomatic nickel) acetylene compounds.

EXAMPLE XXI To 1000 gallons of a gasoline containing 46.2 percent paraffins, 28.4 percent olefins, and 25.4 percent aromatics which has a final boiling point of 390 F. and an API gravity of 590 and which contains three milliliters of tetraethyl-lead as 62-mix (1 theory of ethylene dichloride and 0.5 theory of ethylene d-ibromide) is added suflicient .bis(cyclopentadienyl nickel) pentyne-l to give a nickel concentration of six grams per gallon.

EXAMPLE XXII To a typical aviation fuel having an API gravity of 64.4 and an end boiling point of 335 F. and which contains 8.0 grams of tetraethyllead and one theory of dibromobutane is added a mixture of bis(cyclopentadienyl nickel) pentyne-l and bis(cyclopentadienyl nickel) hexyne-3 in amounts such that two grams of nickel from the pentyne-l compound and one gram of nickel from the hexyne-3 compound are present in the finished fuel.

EXAMPLE XXIII A fluid for addition to gasoline is prepared by admixing tetraethyllead, bis(cyclopentadienyl nickel) hexyne-3 and trimethylphosphate in amount such that for each gram of lead there is 0.01 gram of nickel and 0.1 theory of trimethylphosphate.

To demonstrate the effectiveness of hydrocarbon fuels blended with -bis(cyclomatic nickel) acetylene compounds according to the invention, tests were made on fuels to which no antiknock agent was added and fuels which were blended in accordance with this invention. These tests were conducted according to the Research Method. The Research Method of determining octane number of a fuel is generally accepted as a method of test which gives a good indication of fuel behavior in full scale automotive engines under normal driving conditions and is the method most used by commercial installations in determining the value of a gasoline additive. The Research Method of testing antiknocks is conducted in a single cylinder engine especially designed for this purpose and referred to as the CPR engine. This engine has a variable compression ratio and during the test the temperature of the jacket water is maintained at 212 F. and the inlet air temperature is controlled at F. The engine is operated at a speed of 600 rpm. with a spark advance of 13 before top dead center. The test method employed is more fully described in Test Procedure D-90855 contained in the 1956 edition of ASTM Manual of Engine Test Methods for Rating Fuels. When tested in this manner, it is found that the addition of one gram of nickel per gallon as the compound, bis(cyclopentadienyl nickel) hexyne-3, causes a substantial increase in the octane number of a non-additive containing gasoline.

Further tests which were performed using the Research Method involved the base reference fuels which contained both a lead antiknock and halohydrocarbon scavengers. To the reference fuels was added a typical compound of my invention, bis(cyclopentadienyl nickel) hexyne-3. In each case, a substantial gain in the octane number of the base fuel was noted.

' These results are set forth in the following table. The fuel designated as A in the table comprised 40 percent by volume of toluene, 30 percent by volume of n-heptane, 20 percent by volume of diisobutylene, and 10 volume percent isooctane containing three milliliters of tetraethyllead per gallon as 62-mix. 62-rnix is a commercial antiknock fluid comprising tetraethyllead, 1.0 theory of ethylene dichloride and 0.5 theory of ethylene dibromide. The fuel designated as B is a commercial regular grade fuel containing three milliliters of tetraethyllead per gallon as 62mix, and the fuels designated C, D, E and F, are commercial premium grade fuel containing three milliliters per gallon of tetraethyllead as 62-mix.

Table I.,Research octane number vs. fuel type Concentration of bis(cyclopentadienyl nickel) hexyne-B expressed as grams of nickel per gallon Fuel A 97. 9 99.4 99. 7 99. 7 97. 9 99.3 99. 99. 6 B 93. 7 94. 6 94. 7 94. 9 93. 3 94. 5 94. 4 94. 7 C 98.0 98. 6 98.6 98. 7 98. 1 98. 6 98. 6 98.6 D 98.6 99.4 99.3 99. 4 98.6 99.4 99. 3 99.3 E 99.6 99.9 99.9 100.3 99. 4 99.9 99.9 99. 9 F 100.0 100.6 100.6 100.6 100. 1 100. 7 100. 7 100. 7

Similar results are obtained using concentrations of the nickel additive up to 10 grams of nickel for each gram of lead in the fuel. Also, good results are obtained using other of the nickel compounds of my invention as the antiknock additive.

As shown by the above data, a typical compound of my invention, bis(cyclopentadienyl nickel) heXyne-3, is a very effective supplemental antiknock. As in the case of most supplemental antiknocks, it is generally more effective as a supplement at low concentrations, and its eifectiveness is diminished as its concentration is increased.

Further tests were conducted in a slightly modified version of the single cylinder CFR engine described above. In the modified test version, the fuel is injected directly into the engine cylinder rather than being induced via a carburetor. In addition, the fuel is continually recirculated prior to injection into the cylinder so as to minimize any precipitation of the additive from the fuel. In this modified test, the single cylinder CPR engine is operated under the following conditions:

Speed900 r.p.m.

Spark plug gap.025"

Ignition timing20 B.T.D.C. Ignition breaker point gap-.0l5" Jacket cooling temp.l48 F. Crankcase oil temp.l25 F. Inlet air temp.l1-0 F.

Inlet valve lash-.005"

Exhaust valve lash-.010" Injection nozzle pop-off pressurell00 p.s.i Injection timing-140 A.T.D.C.

When tested in the above manner in the modified CPR injector engine, the following results were obtained using reference fuel A as described previously with respect to Table I.

As shown by the above table, compounds of my in-' vention prove extremely effective as supplemental antiknocks when tested in the modified CFR injector englue. and II, the modified injector engine rating is extremely sensitive. Consequently, the increase in octane number, noted in this type of test, is larger than would generally be observed in the Research Method used in establishing the data for Table I.

A further use for my compounds is in gas phase metal plating. In this application, the compounds are thermally decomposed in an atmosphere of a reducing gas such as hydrogen or a neutral atmosphere such as nitrogen to form metallic films on a sub-strate material. These films have a wide variety of applications. They may be used in forming conductive surfaces such as employed in a printed circuit, in producing a decorative effect on a sub-strate material, or in applying a corrosion-resistant coating to a sub-strate material.

The compounds of my invention also find application as additives to distillate fuels used in home heating, and as additives to lubricating oils and greases to impart improved lubricity characteristics thereto. Further, my compounds may be incorporated in paints, varnish, printing inks, synthetic resins of the drying oil type, oil enamels and the like to impart improved drying characteristics to such compositions. Other important uses of my compounds include their use as chemical intermediates in the preparation of metal-containing polymeric materials. Also, some of the metallic derivatives of my invention can be employed in the manufacture of medicinals and other therapeutic materials, as well as in agricultural chemicals such, as, for example, fungicides, de' foliants, growth regulants, and the like. In addition to the use of my compounds in reducing smoke and soot when used as additives in distillate fuels used in home heating, they are also useful as additives to jet fuels and diesel fuels in reducing smoke and soot.

Having fully defined the novel compounds of my invention, their mode of preparation and their manifold utilities, I desire to be limited only within the lawful scope of the appended claims.

I claim:

1. An improved fuel comprising a liquid hydrocarbon of the gasoline boiling range containing from 0.05 to about 10 grams per gallon of nickel as a compound having the formula wherein Q and Q are selected from the group consisting of hydrogen and univalent hydrocarbon radicals containing from one to about 10 carbon atoms, Cy and Cy are cyclopentadienyl hydrocarbon moieties which each donate five electrons to the nickel atom for bonding, and each of the two nickel atoms present in the molecule achieves the inert gas electron configuration of krypton.

2. The improved fuel of claim 1 wherein the nickel content ranges from about 1.0 to about 6.0 grams of nickel per gallon.

3. The improved fuel of claim 2 wherein the bridging actylenic group present in the nickel compound contains from 4 to 10 carbon atoms.

4. The composition of claim 3 wherein the bridging As will be noted by a comparison of Tables I 15 acetylenic group in the nickel compound contains 6 carbon atoms.

5. The composition of claim 4 wherein the nickel is present in the form of a bis(cyclopentadienyl nickel) hexyne-3 compound.

6. An improved fuel composition comprising a liquid hydrocarbon of the gasoline boiling range containing up to about 8 grams of lead per gallon as an organolead antiknock agent, and from about 0.008 to about 10 grams of nickel as a bis (cyclopentadienyl nickel) acetylenic compound for each gram of lead present in the fuel.

7. The composition of claim 6 wherein the bridging acetylenic group in the bis(cyclopentadienyl nickel) acetylene compound contains from 4 to about 10 carbon atoms and there is also present a scavenger for the origanolead compound.

8. An antiknock fluid comprising an organolead antiknock compound and from about 0.008 to about 10 grams of nickel as a bis(cyclopentadienyl nickel) acetylenic compound for eachgram of lead as an organolead compound.

9. The antiknock fluid of claim 8 wherein the bridging group in the bis(cyclopentadienyl nickel) acetylenic compound contains from 4 to 10 carbon atoms and there is also present a scavenger for the organolead compound.

'10. The fuel of claim 1 wherein said nickel compound is bis(cyclopentadienyl nickel) acetylene.

11. The composition of claim 4 wherein said nickel compound is bis(cyclopentadienyl nickel) propyne.

12. The composition of claim 4 wherein said nickel compound is bis(cyclopentadienyl nickel) pentyne-l.

13. The composition of claim 6 wherein said nickel compound is bis(cyclopentadienyl nickel) heXyne-3.

14. The composition of claim 6 wherein said nickel compound is bis(cyclopentadienyl nickel) propyne.

References Cited by the Examiner UNITED STATES PATENTS 3,006,742 10/1961 Brown 4468 X 3,032,572 5/1962 Fischer 4468 X 3,052,704 9/1962 Benson 4468 X 3,060,214 10/1962 Cordes 252386 X DANIEL E. WYMAN, Primary Examiner. 

1. AN IMPROVED FUEL COMPRISING A LIQUID HYDROCARBON OF THE GASOLINE BOILING RANGE CONTAINING FROM 0.05 TO ABOUT 10 GRAMS PER GALLON OF NICKEL AS A COMPOUND HAVING THE FORMULA
 6. AN IMPROVED FUEL COMPOSITION COMPRISING A LIQUID HYDROCARBON OF THE GASOLINE BOILING RANGE CONTAINING UP TO ABOUT 8 GRAMS OF LEAD PER GALLON AS AN ORGANOLEAD ANTIKNOCK AGENT, AND FROM ABOUT 0.008 TO ABOUT 10 GRAMS OF NICKEL AS A BIS(CYCLOPENTADIENYL NICKEL) ACETYLENIC COMPOUND FOR EACH GRAM OF LEAD PRESENT IN THE FUEL. 